jsflash.c

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#if 0
	/*
	 * This code is ok, except that counter based timeout
	 * has no place in this world. Let's just drop timeouts...
	 */
	{
		int i;
		__u32 x;
		for (i = 0; i < 1000000; i++) {
			x = jsf_inl(p);
			if ((x & 0x80808080) == 0x80808080) break;
		}
		if ((x & 0x80808080) != 0x80808080) {
			printk("jsf0: erase timeout with 0x%08x\n", x);
		} else {
			printk("jsf0: erase done with 0x%08x\n", x);
		}
	}
#else
	jsf_wait(p);
#endif

	return 0;
}

/*
 * Program a block of flash.
 * Very simple because we can do it byte by byte anyway.
 */
static int jsf_ioctl_program(unsigned long arg)
{
	struct jsflash_program_arg abuf;
	char *uptr;
	unsigned long p;
	unsigned int togo;
	union {
		unsigned int n;
		char s[4];
	} b;

	if (verify_area(VERIFY_READ, (void *)arg, JSFPRGSZ))
		return -EFAULT; 
	copy_from_user(&abuf, (char *)arg, JSFPRGSZ);
	p = abuf.off;
	togo = abuf.size;
	if ((togo & 3) || (p & 3)) return -EINVAL;

	uptr = (char *) (unsigned long) abuf.data;
	if (verify_area(VERIFY_READ, uptr, togo))
		return -EFAULT;
	while (togo != 0) {
		togo -= 4;
		copy_from_user(&b.s[0], uptr, 4);
		jsf_write4(p, b.n);
		p += 4;
		uptr += 4;
	}

	return 0;
}

static int jsf_ioctl(struct inode *inode, struct file *f, unsigned int cmd,
    unsigned long arg)
{
	int error = -ENOTTY;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;
	switch (cmd) {
	case JSFLASH_IDENT:
		if (verify_area(VERIFY_WRITE, (void *)arg, JSFIDSZ))
			return -EFAULT; 
		copy_to_user(arg, &jsf0.id, JSFIDSZ);
		error = 0;
		break;
	case JSFLASH_ERASE:
		error = jsf_ioctl_erase(arg);
		break;
	case JSFLASH_PROGRAM:
		error = jsf_ioctl_program(arg);
		break;
	}

	return error;
}

static int jsfd_ioctl(struct inode *inode, struct file *file,
    unsigned int cmd, unsigned long arg)
{
	int dev;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;
	if (!inode)
		return -EINVAL;
	if ((dev = MINOR(inode->i_rdev)) >= JSF_MAX) return -ENODEV;

	switch (cmd) {
	case BLKGETSIZE:
		return put_user(jsfd_bytesizes[dev] >> 9, (long *) arg);

#if 0
	case BLKROSET:
	case BLKROGET:
	case BLKSSZGET:
		return blk_ioctl(inode->i_rdev, cmd, arg);
#endif

	/* case BLKFLSBUF: */	/* Program, then read, what happens? Stale? */
	default: ;
	}
	return -ENOTTY;
}

static int jsf_mmap(struct file * file, struct vm_area_struct * vma)
{
	return -ENXIO;
}

static int jsf_open(struct inode * inode, struct file * filp)
{

	if (jsf0.base == 0) return -ENXIO;
	if (test_and_set_bit(0, (void *)&jsf0.busy) != 0)
		return -EBUSY;

	return 0;	/* XXX What security? */
}

static int jsfd_open(struct inode *inode, struct file *file)
{
	struct jsfd_part *jdp;
	int dev;

	if (!inode)
		return -EINVAL;
	dev = MINOR(inode->i_rdev);
	if (dev >= JSF_MAX || (dev & JSF_PART_MASK) >= JSF_NPART) {
		printk(KERN_ALERT "jsfd_open: illegal minor %d\n", dev);
		return -ENODEV;
	}

	jdp = &jsf0.dv[dev];
	jdp->refcnt++;

	MOD_INC_USE_COUNT;
	return 0;
}

static int jsf_release(struct inode *inode, struct file *file)
{
	lock_kernel();
	jsf0.busy = 0;
	unlock_kernel();
	return 0;
}

static int jsfd_release(struct inode *inode, struct file *file)
{
	struct jsfd_part *jdp;
	int dev;

	if (!inode)
		return -ENODEV;
	dev = MINOR(inode->i_rdev);
	if (dev >= JSF_MAX || (dev & JSF_PART_MASK) >= JSF_NPART) {
		printk(KERN_ALERT "jsfd_release: illegal minor %d\n", dev);
		return -ENODEV;
	}

	jdp = &jsf0.dv[dev];
	if (jdp->refcnt <= 0) {
		printk(KERN_ALERT "jsfd_release: bad ref on minor %d\n", dev);
	} else {
		--jdp->refcnt;
	}
	/* N.B. Doesn't lo->file need an fput?? */
	MOD_DEC_USE_COUNT;
	return 0;
}

static struct file_operations jsf_fops = {
	owner:		THIS_MODULE,
	llseek:		jsf_lseek,
	read:		jsf_read,
	write:		jsf_write,
	ioctl:		jsf_ioctl,
	mmap:		jsf_mmap,
	open:		jsf_open,
	release:	jsf_release,
};

static struct miscdevice jsf_dev = { JSF_MINOR, "jsflash", &jsf_fops };

static struct block_device_operations jsfd_fops = {
	open:		jsfd_open,
	release:	jsfd_release,
	ioctl:		jsfd_ioctl,
};

EXPORT_NO_SYMBOLS;

int jsflash_init(void)
{
	int rc;
	struct jsflash *jsf;
	int node;
	char banner[128];
	struct linux_prom_registers reg0;

	node = prom_getchild(prom_root_node);
	node = prom_searchsiblings(node, "flash-memory");
	if (node != 0 && node != -1) {
		if (prom_getproperty(node, "reg",
		    (char *)&reg0, sizeof(reg0)) == -1) {
			printk("jsflash: no \"reg\" property\n");
			return -ENXIO;
		}
		if (reg0.which_io != 0) {
			printk("jsflash: bus number nonzero: 0x%x:%x\n",
			    reg0.which_io, reg0.phys_addr);
			return -ENXIO;
		}
		/*
		 * Flash may be somewhere else, for instance on Ebus.
		 * So, don't do the following check for IIep flash space.
		 */
#if 0
		if ((reg0.phys_addr >> 24) != 0x20) {
			printk("jsflash: suspicious address: 0x%x:%x\n",
			    reg0.which_io, reg0.phys_addr);
			return -ENXIO;
		}
#endif
		if ((int)reg0.reg_size <= 0) {
			printk("jsflash: bad size 0x%x\n", (int)reg0.reg_size);
			return -ENXIO;
		}
	} else {
		/* XXX Remove this code once PROLL ID12 got widespread */
		printk("jsflash: no /flash-memory node, use PROLL >= 12\n");
		prom_getproperty(prom_root_node, "banner-name", banner, 128);
		if (strcmp (banner, "JavaStation-NC") != 0 &&
		    strcmp (banner, "JavaStation-E") != 0) {
			return -ENXIO;
		}
		reg0.which_io = 0;
		reg0.phys_addr = 0x20400000;
		reg0.reg_size  = 0x00800000;
	}

	/* Let us be really paranoid for modifications to probing code. */
	/* extern enum sparc_cpu sparc_cpu_model; */ /* in <asm/system.h> */
	if (sparc_cpu_model != sun4m) {
		/* We must be on sun4m because we use MMU Bypass ASI. */
		return -ENXIO;
	}

	if (jsf0.base == 0) {
		jsf = &jsf0;

		jsf->base = reg0.phys_addr;
		jsf->size = reg0.reg_size;

		/* XXX Redo the userland interface. */
		jsf->id.off = JSF_BASE_ALL;
		jsf->id.size = 0x01000000;	/* 16M - all segments */
		strcpy(jsf->id.name, "Krups_all");

		jsf->dv[0].dbase = jsf->base;
		jsf->dv[0].dsize = jsf->size;
		jsf->dv[1].dbase = jsf->base + 1024;
		jsf->dv[1].dsize = jsf->size - 1024;
		jsf->dv[2].dbase = JSF_BASE_ALL;
		jsf->dv[2].dsize = 0x01000000;

		printk("Espresso Flash @0x%lx [%d MB]\n", jsf->base,
		    (int) (jsf->size / (1024*1024)));
	}

	if ((rc = misc_register(&jsf_dev)) != 0) {
		printk(KERN_ERR "jsf: unable to get misc minor %d\n",
		    JSF_MINOR);
		jsf0.base = 0;
		return rc;
	}

	return 0;
}

int jsfd_init(void) {
	struct jsflash *jsf;
	struct jsfd_part *jdp;
	int i;

	if (jsf0.base == 0) {
		return -ENXIO;
	}

	if (register_blkdev(JSFD_MAJOR, "jsfd", &jsfd_fops)) {
		printk("jsfd_init: unable to get major number %d\n",
		    JSFD_MAJOR);
		return -EIO;
	}

	blksize_size[JSFD_MAJOR] = jsfd_blksizes;
	blk_size[JSFD_MAJOR] = jsfd_sizes;

	blk_init_queue(BLK_DEFAULT_QUEUE(MAJOR_NR), DEVICE_REQUEST);
	/* blk_queue_headactive(BLK_DEFAULT_QUEUE(MAJOR_NR), 0); */
	for (i = 0; i < JSF_MAX; i++) {
		if ((i & JSF_PART_MASK) >= JSF_NPART) continue;
		jsf = &jsf0;	/* actually, &jsfv[i >> JSF_PART_BITS] */
		jdp = &jsf->dv[i&JSF_PART_MASK];

		jdp->refcnt = 0;

		jsfd_blksizes[i] = 1024;
		jsfd_bytesizes[i] = jdp->dsize;
		jsfd_sizes[i] = jsfd_bytesizes[i] >> 10;
		register_disk(NULL, MKDEV(JSFD_MAJOR, i), 1, &jsfd_fops,
				jsfd_bytesizes[i] >> 9);
		set_device_ro(MKDEV(JSFD_MAJOR, i), 1);
	}
	return 0;
}

#ifdef MODULE

int init_module(void) {
	int rc;

	if ((rc = jsflash_init()) == 0) {
		jsfd_init();
		return 0;
	}
	return rc;
}

void cleanup_module(void) {

	/* for (all probed units) {  } */
	if (jsf0.busy)
		printk("jsf0: cleaning busy unit\n");
	jsf0.base = 0;
	jsf0.busy = 0;

	misc_deregister(&jsf_dev);
	if (unregister_blkdev(JSFD_MAJOR, "jsfd") != 0)
		printk("jsfd: cleanup_module failed\n");
	blk_cleanup_queue(BLK_DEFAULT_QUEUE(MAJOR_NR));
}
#endif